The application relates to a split application of Chinese patent application with the application date of 2022, 10-month and 23-day, the application number of 202280007469.0 and the name of 'compact double-folding long-focus camera'.
Disclosure of Invention
In various exemplary embodiments, a camera module is provided, including a lens barrel having n=6 lens elements Li, 6 lens elements Li being divided into a first lens group (G1) and a second lens group (G2), and the lens barrel having an effective focal length EFL, an aperture diameter DA, an f-number f/#, an optical total length TTL, and a back focal length BFL, wherein each lens element has a respective focal length fi, and wherein the first lens element L1 faces an object side and the last lens element LN faces an image side, an object-side optical path folding element O-OPFE for folding a first optical path (OP 1) to a second optical path (OP 2), an image-side optical path folding element I-OPFE for folding OP2 to a third optical path (OP 3), wherein OP1 and OP2 are perpendicular to each other, and wherein OP1 and OP3 are parallel to each other, and an image sensor having a Sensor Diagonal (SD). The camera module is a folded digital camera module, wherein G1 is located at an object side of the O-OPFE and G2 is located at an image side of the O-OPFE, wherein EFL is in the range of 8mm < EFL <50mm, wherein the camera module is divided into a first region having a minimum camera module region height MHM and comprising G1 and O-OPFE and a second region having a minimum shoulder region height MHS<MHM and comprising I-OPFE and an image sensor, wherein all heights are measured along OP1, wherein the aperture height of the lens is HL, and wherein HL/MHS >0.9.
In some examples, HL/MHS >1. In some examples, HL/MHS >1.05. In some examples, HL/MHS >1.1.
In some examples, EFL > 1.1.MLM. In some examples, EFL > 1.2.MLM. In some examples, EFL > 1.3.MLM.
In some examples, 5mm < sd <15mm.
In some examples, SD/EFL >0.3. In some examples, SD/EFL >0.35. In some examples, SD/EFL >0.4.
In some examples, the ratio between the optical width WL of the lens and the optical height HL of the lens satisfies WL/HL >1.1. In some examples, WL/HL >1.2.
In some examples, EFL/TTL <1.2.
In some examples, BFL/EFL >0.25. In some examples, BFL/TTL >0.3.
In some examples, 15mm < EFL <40mm. In some examples, 20mm < EFL <30mm.
In some examples, 5mm < DA <15mm, and 2<f/# 6.5. In some examples, 6mm < da <10mm and 2.5< f/# <4.5.
In some examples, G1, O-OPFE, and G2 are movable along OP2 relative to the I-OPFE and the image sensor together for focusing.
In some examples, G1, O-OPFE, G2, and I-OPFE are movable along OP2 with respect to the image sensor for Optical Image Stabilization (OIS) about the first OIS axis.
In some examples, G1, O-OPFE, and G2 are movable along OP2 with respect to the image sensor for OIS about the first OIS axis.
In some examples, G1, O-OPFE, G2, and I-OPFE are movable with respect to the image sensor along an axis perpendicular to both OP1 and OP2 for OIS about a second OIS axis.
In some examples, G1, O-OPFE, and G2 are movable along OP2 with respect to the image sensor for OIS about the second OIS axis.
In some examples, the first region of the camera module has a module region height HM, the second region of the camera module has a shoulder region height HS, and HM>HS. In some examples, 4mm < hS <10mm and 6mm < hM <13mm. In some examples, 6mm < hS <8mm and 7mm < hM <11mm.
In some examples, HS/HM <0.9. In some examples, HS/HM <0.8.
In some examples, the ratio between TTL and the Average Lens Thickness (ALT) of all lens elements L1 to LN satisfies ALT/TTL <0.05. In some examples, the ratio of thickness (T1) and ALT of L1 satisfies T1/ALT >2.
In some examples, distances d5-6 and ALT between L5 and L6 satisfy d5-6/ALT >1.2.
In some examples, L1 is made of glass.
In some examples, the ratio between EFL and f1 of L1 satisfies f1/EFL <0.75.
In some examples, the ratio between EFL and |f6| of L6 satisfies |f6|/EFL >0.75.
In some examples, the last lens element LN is negative.
In some examples, G1 has a thickness T-G1 and T-G1/TTL <0.1.
In some examples, G2 has a thickness T-G2 and T-G2/TTL <0.1.
In some examples, G1 is a dicing lens that cuts along an axis parallel to OP 1.
In some examples, G1 is cut 20% and MH is reduced by >10% relative to an axially symmetric lens group having the same lens diameter as the cut G1 measured along an axis perpendicular to both OP1 and OP 2.
In some examples, the O-OPFE and/or I-OPFE are mirrors.
In some examples, G2 is a dicing lens that cuts along an axis parallel to OP 2.
In some examples, G2 is cut 20% and has a cut lens diameter, and MH is reduced by >10% relative to an axially symmetric lens through the cut, the axially symmetric lens having the same lens diameter as the diameter of the cut lens measured along an axis perpendicular to both OP1 and OP 2.
In some examples, the camera module does not include an I-OPFE.
In some examples, OP1 and OP3 are perpendicular to each other.
In various exemplary embodiments, a mobile device is provided comprising a camera module as described above, wherein the mobile device has a device thickness T and a camera raised area, wherein the raised area has a raised height t+b, wherein a first area of the camera module is incorporated into the camera raised area, and wherein a second area of the camera module is not incorporated into the camera raised area.
In some examples, the first region of the camera includes a camera module lens, and wherein the second region of the camera includes a camera module image sensor.
In various exemplary embodiments, a lens is provided having n=4 lens elements Li with lens thicknesses TLens, EFL, aperture diameters DA, f/#, TTL, and BFL, wherein each lens element has a respective focal length fi, and wherein a first lens element L1 faces the object side and a last lens element LN faces the image side, an O-OPFE for folding a first optical path (OP 1) to a second optical path (OP 2), an I-OPFE for folding OP2 to a third optical path (OP 3), wherein OP1 and OP2 are perpendicular to each other and wherein OP1 and OP3 are parallel to each other, and an image sensor with a sensor diagonal SD. The camera module is a folded digital camera module, wherein the lens is located at an object side of the O-OPFE, wherein EFL is in the range of 8mm < EFL <50mm, and wherein the ratio between the lens thickness TLens and TTL satisfies TLens/TTL <0.4.
In some examples, TLens/TTL <0.3. In some examples, TLens/TTL <0.25.
In some examples, the camera module is divided into a first region having a minimum camera module region height MHM and comprising a lens and an O-OPFE and a second region having a minimum shoulder region height MHS<MHM and comprising an I-OPFE and an image sensor, the camera module having a minimum camera module length MLM, wherein all heights are measured along OP1, wherein the length is measured along OP2, wherein the aperture height of the lens is HL, and wherein HL>MHS -1.5mm.
In some examples, HL>MHS -1mm.
In some examples, HL>0.8·MHS. In some examples, HL>0.9·MHS. In some examples, HL>MHS.
In some examples, EFL > 1.1.MLM. In some examples, EFL > 1.2.MLM. In some examples, EFL > 1.3.MLM.
In some examples, TTL > 1.2.MLM. In some examples, TTL > 1.3.MLM. In some examples, TTL > 1.4.MLM.
In some examples, the lens and the O-OPFE are movable along OP2 with respect to the I-OPFE and the image sensor for focusing.
In some examples, the lens is movable along OP1 relative to the O-OPFE, I-OPFE, and image sensor for focusing.
In some examples, the lens, O-OPFE, and I-OPFE are movable together along OP2 with respect to the image sensor for OIS about the first OIS axis.
In some examples, the lens is movable along OP2 relative to the O-OPFE, I-OPFE, and image sensor for OIS about the first OIS axis.
In some examples, the lens, O-OPFE, and I-OPFE are movable with respect to the image sensor along an axis perpendicular to both OP1 and OP2 for OIS about a second OIS axis.
In some examples, the lens is movable relative to the O-OPFE, I-OPFE, and image sensor along an axis perpendicular to both OP1 and OP2 for OIS about a second OIS axis.
In some examples, L1 is made of glass and has a refractive index n with n > 1.7.
In some examples, f1< EFL/2.
In some examples, the sequence of powers of lens elements L1 to L4 is positive-negative-positive. In some examples, the sequence of powers of lens elements L1 to L4 is positive-negative-positive-negative. In some examples, the sequence of powers of lens elements L1 to L4 is positive-negative-positive.
Detailed Description
In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding. However, it will be understood by those skilled in the art that the presently disclosed subject matter may be practiced without these specific details. In other instances, well-known methods and features have not been described in detail so as not to obscure the presently disclosed subject matter.
Fig. 2A schematically illustrates an embodiment of a "2-group" (or "2G") dual-folded telephoto camera module disclosed herein and designated by the reference numeral 200. The camera module 200 includes a lens 202 having a plurality (N) of lens elements (here and for example, n=5) numbered L1 to LN, with L1 oriented toward the object side. The camera module 200 also includes an O-OPFE 204 for folding the first optical path OP1212 to the second optical path OP2 214, an I-OPFE 206 for folding OP2 to the third optical path OP3 216, and an image sensor 208. As shown, camera elements may be included in the module housing 220. In camera 200, OP1212 is substantially parallel to the z-axis, OP2 214 is substantially parallel to the y-axis, and OP3 216 is substantially parallel to the z-axis. O-OPFE 204 and I-OPFE 206 form a 45 degree angle with both the y-axis and the z-axis. The image sensor 208 is oriented in a plane perpendicular to the z-axis in the coordinate system shown.
In other examples, a camera module such as camera module 200 may not be a dual folded telephoto camera module, but a (single) folded telephoto camera module. That is, the camera module may not have OP3 and may not include I-OPFE such as I-OPFE 206. In these other examples, OP1 may be oriented perpendicular to OP2 (as shown), and an image sensor (such as image sensor 208) may be oriented in a plane perpendicular to the y-axis in the coordinate system shown.
In further examples, a camera module such as camera module 200 may be a dual-folded telephoto camera module, but OP3 may be perpendicular to OP1 (not parallel to OP1, as shown). In these additional examples, OP1 may be parallel to the z-axis, OP2 may be parallel to the y-axis (as shown), and OP3 may be perpendicular to the y-z coordinate system shown. An image sensor, such as image sensor 208, may be oriented in a plane parallel to the y-z coordinate system shown.
The lens 202 is divided into a first lens group ("G1") and a second lens group ("G2"), labeled 202-G1 and 202-G2. G1 is located on the object side of O-OPFE 204 and G2 is located on the image side of O-OPFE 204 and on the object side of I-OPFE 206.
The camera module 200 is divided into a first "module" region comprising 202-G1 and O-OPFE 204 and having a module region height HM and a minimum module region length MRLM (as shown), and a second "shoulder" region comprising I-OPFE 206 and image sensor 208 and having a shoulder region height HS<HM and a shoulder region length LS. All heights are measured along OP1 212 and all lengths are measured along OP2 214.
The optical height and optical width of lens element L1 may define the aperture (having diameter DA) of camera 200, such that the optical height and optical width of lens element L1 also represent the aperture height and aperture width, respectively. As shown, the height HL1 of the lens element L1 is measured along the y-axis. This fact and further design considerations disclosed herein allow for the implementation of optical systems that provide low f/# and large EFL (i.e., high zoom factors) because of their compact or dimensional size. This is expressed in terms of two advantageous values and ratios (see table 1):
1. Optical height HL, which is greater than 90%, HL>0.9·MHS, or even the minimum shoulder height MHS
HL>MHS;
EFL, which is 10% (or 20%, or even 30%) greater than the minimum module length, EFL >1.1·mlM.
As shown, the TTL of the camera module 200 is divided into three parts, TTL1 through TTL3. BFL of camera module 200 is split into two parts, BFL1 and BFL2. The first part TTL1 is parallel to OP1 212, the second part TTL2 and the first part BFL1 are parallel to OP2 214, and the third part TTL3 and the second part BFL2 are parallel to OP3 216. TTL and BFL are respectively controlled by ttl=ttl1+ttl 2+ttl3 and bfl=bfl 1+bfl2.
To estimate the theoretical limit of the minimum size of a camera module comprising the optical lens system disclosed herein, we introduce the following parameters and correlations. "theoretical limit" means an optical operation region in which only the components included in the optical lens system disclosed herein are considered.
Minimum module area length MRLM
MRLM is the theoretical module area length limit for module area 222 having height HM. MRL (MRL)M
Defined by the physical dimensions of the components included in the module region 222.
For 200, MRLM＝HG1, the height of G1 (height measured along the y-axis) represents the lower limit of MRLM.
Shoulder area length LS
The length of the shoulder region 224 with a height HS.
Obtained from MLS. To achieve an actual estimate of the camera shoulder length ("LS"), a length of, for example, 3.5mm may be added to MLS, i.e., LS＝MLS +3.5mm. This additional length allows for movement strokes that may be required for AF and/or OIS, image sensor packaging, outer body, etc. It is noted that the number of the components,
The value of 3.5mm is exemplary and in no way limiting, and the additional value may be at 1.5mm
And 10 mm.
In general, it may be beneficial from an industrial design point of view to maximize LS (minimize MLM).
Minimum module height ("MHM") and module height HM
MHM is the theoretical module height limit of module region 222 having height HM -MHM＝HOPFE+ΔLO+TG1,HOPFE is the height of O-OPFE 204 in a direction parallel to OP1 112 (O-OPFE 204 is oriented at 45 degrees with respect to both the y-axis and the z-axis such that HOPFE = WOPFE) WOPFE is the width of O-OPFE in a direction parallel to OP2 214, Δlo is the distance between the central portion of G1 and O-OPFE 204, and TG1 is the height (or thickness) of G1.
To achieve a practical estimation of the camera module height, we calculate HM, i.e. HM＝MHM +1.5mm, by adding an additional height constraint of 1.5mm to MHM. This constraint takes into account the movements that may be required of the Optical Image Stabilization (OIS), autofocus (AF), housing, lens cover, etc.
Note that the value of 1.5mm is exemplary and not limiting, and that the additional value may vary between 0.5mm and 3 mm.
Minimum Module Length ("MLM")
MLM is the theoretical module length limit for module housing 220 having height HM.
MLM＝MRLM+MLS。
To achieve an actual estimate of the camera module length ("LM"), a length of, for example, 3.5mm may be added to MLM, i.e. LM＝MLM +3.5mm.
Minimum shoulder height ("MHS") and shoulder height HS
MHS is the theoretical shoulder height limit of shoulder region 224 with height HS.
To achieve a practical estimation of the shoulder height HS, we add an additional height of 1.5mm to MHS
HS, i.e., HS＝MHS +1.5mm, was calculated as above.
In contrast to known folded cameras like the camera 100, in the camera module 200 the image sensor 208 is not oriented parallel to the z-axis, but rather to the y-axis (in the coordinate system shown). Given a particular HS, this allows the use of a larger image sensor, for example, an image sensor with a Sensor Diagonal (SD) in the range of about 6mm to 16mm, since the size of the image sensor is not limited by HS. Larger image sensors are beneficial in terms of the image quality of the camera, e.g., measured in terms of signal-to-noise ratio ("SNR").
Fig. 2B schematically illustrates a cross-section of a mobile device 230 (e.g., a smartphone) having an exterior front surface 232 and an exterior rear surface 234, the exterior rear surface 234 comprising the 2G dual-folded telephoto camera 200. The aperture of camera 200 is located at rear surface 234. The front surface 232 may, for example, include a screen (not visible). The mobile device 230 has a first "regular" region 236 having a thickness ("T") and a second "raised" region 238 that is raised (protruding outward) a height B above the regular region 236. The bump region has a bump length ("BL") and a bump thickness T+B. The module region 222 of the camera 200 is included in the raised region 238. Shoulder regions 224 are included in regular regions 236. Optionally, in some embodiments, portions of shoulder region 224 may also be included in raised region 238.
For industrial design reasons, a small camera bump area (i.e., short BL) is desirable. A known folded camera such as 100 may be fully included in raised region 238. In contrast, camera 200 (which may be only partially contained in raised region 238) allows for a smaller camera raised region (i.e., a shorter BL).
Fig. 2C schematically illustrates an embodiment of a "group 1" (or "1G") dual-folded telephoto camera module disclosed herein and labeled 250. The camera module 250 includes a lens 252 having a plurality (N) of lens elements (here and for example n=3) numbered L1 to LN, and L1 is oriented toward the object side. The camera module 250 also includes an O-OPFE 254 for folding OP1 262 to OP2 264, an I-OPFE 256 for folding OP2 to OP3 266, and an image sensor 258. The camera element may be included in the module housing 270. In camera 250, OP1 262 is substantially parallel to the z-axis, OP2 264 is substantially parallel to the y-axis, and OP3 266 is substantially parallel to the z-axis. O-OPFE 254 and I-OPFE 256 may or may not form 45 degrees with the y-axis and the z-axis. Lens 252 is located entirely on the object side of O-OPFE 254. The image sensor 258 is oriented in a plane perpendicular to the z-axis in the coordinate system shown.
In other examples, a camera module such as camera module 250 may not be a dual folded telephoto camera module, but rather a (single) folded telephoto camera module. That is, it may not have OP3, and it may not include an I-OPFE, such as I-OPFE 256. In these other examples, OP1 may be oriented perpendicular to OP2 (as shown), and an image sensor (such as image sensor 208) may be oriented in a plane perpendicular to the y-axis in the coordinate system shown.
In further examples, a camera module such as camera module 250 may be a dual-folded telephoto camera module, but OP3 may be perpendicular to OP1 (not parallel to OP1, as shown). In these additional examples, OP1 may be parallel to the z-axis, OP2 may be parallel to the y-axis (as shown), and OP3 may be perpendicular to the y-z coordinate system as shown. An image sensor, such as image sensor 258, may be oriented in a plane parallel to the y-z coordinate system shown.
The optical height and optical width of lens element L1 may define the aperture of camera 250. As shown, the height HL1 of the lens element L1 is measured along the y-axis. This fact and further design considerations disclosed herein allow for the implementation of optical systems that provide low f/#, large EFL (i.e., high zoom factor), and large TTL because they have compact or dimensional dimensions. Furthermore, the lens thickness occupies only a relatively small portion of the TTL. This is expressed in terms of the following four advantageous values and ratios (see table 1):
1. Optical height HL, which is greater than 80% of minimum shoulder height MHS, HL >0.8·mhS.
EFL, which is 10% (or 20%, or even 30%) greater than the minimum module length, EFL >1.1·mlM.
TTL, which is 20% (or 30%, or even 40%) greater than the minimum module length, TTL >1.2·mlM.
4. A small ratio of lens thickness TLens to total optical length, TLens/TTL <0.4 (or <0.35, or even
<0.3)。
The camera module 250 is divided into a module region having a module region height HM and including the lens 252 and the O-OPFE 254, and a shoulder region having a shoulder region height HS<HM and including the I-OPFE 256 and the image sensor 258.
As shown, the TTL and BFL of the camera module 250 are divided into three parts, TTL1 to TTL3 and BFL1 to BFL3, respectively. TTL and BFL are respectively controlled by ttl=ttl1+ttl2+ttl 3 and bfl=bfl1+bfl 2+bfl3.
Fig. 2D schematically illustrates a cross-section of a mobile device 280 (e.g., a smartphone) having an exterior front surface 282 and an exterior rear surface 284, the exterior rear surface 284 comprising the dual-folded telephoto camera 250. An aperture (aperture) of the camera 250 is located at the rear surface 284. The front surface 282 may, for example, include a screen (not visible). The mobile device 280 has a raised region 288 and a regular region 286 having a thickness ("T"). The bump area has a bump length ("BL") and a bump thickness T+B. The module region 272 of the camera 250 is included in the raised region 288. The shoulder region 274 is included in the regular region 286. Optionally, in some embodiments, portions of the shoulder region 274 may also be included in the raised region 288.
The camera 250 (which may be only partially included in the raised area 288) allows for a relatively small camera raised area (i.e., short BL).
For clarity, all of the camera modules and optical lens systems disclosed herein are advantageous for use in mobile devices (such as smartphones, tablets, etc.).
Fig. 3A to 3D and fig. 4 to 7A illustrate the optical lens system disclosed herein. All of the lens systems shown in fig. 3A to 3D and 4 to 7A may be included in a dual folded camera module (such as 200 or 250 shown in fig. 2A to 2D). In all of the optical lens systems disclosed below, the optical height and optical width of the lens element L1 define the aperture of the optical lens system.
Table 1 summarizes the values of the features included in the lens systems 300, 320, 350, 400, 500, 600, and 700 shown in fig. 3A to 3E and fig. 4 to 7A and their ratios (HL1、WL1、DA、MHS、MHM、HS、HM、ΔLO、TTL1、BFL1、TTL2、BFL2、TTL3、TTL、BFL、EFL、EFL-G1、EFL-G2、SD、ALT、d5-6、f1、f6、T1、MLM、LM、MHM、MHS、T-G1、T-G2 given in mm, HFOV given in degrees).
"Type" designates whether the optical lens system is a 1G or 2G optical lens system.
N designates the number of lens elements.
DA is the pore diameter. For the cut lenses 352, 402 and 702, the effective aperture diameters are given. "effective aperture diameter" herein refers to the diameter of a circular (or axisymmetric) aperture having the same aperture area as a dicing lens (which has a non-axisymmetric aperture).
EFL-G1 and EFL-G2 are the effective focal lengths of the lens groups G1 and G2, respectively.
Average lens thickness ("ALT") the average thickness of all lens elements is measured.
Average gap thickness ("AGT") measures the average thickness of all gaps between lens elements located on the object side of the mirror.
-D5-6 is the distance between L5 and L6.
T1, T-G1 and T-G2 are the central thicknesses of L1, G1 and G2, respectively. For a 1G optical lens system, T-g1=tLens,TLens is the thickness of the lens.
In other examples, HL1 may be in the range of HL1 =4 mm-15 mm.
All other parameters not specifically defined herein have their usual meaning as known in the art.
TABLE 1
Fig. 3A illustrates an embodiment of an optical lens system disclosed herein and designated 300. Lens system 300 includes a lens 302, an O-OPFE 304 (e.g., a prism or mirror), an I-OPFE 306 (e.g., a prism or mirror), an optical element 307, and an image sensor 308. The system 300 is shown with ray tracing. The optical element 307 is optional for all subsequent optical lens systems and may be, for example, an Infrared (IR) filter and/or a glass image sensor dust cap.
O-OPFE 304 and I-OPFE 306 are both oriented at 45 degrees relative to the y-axis and the z-axis. For all subsequent optical lens systems, MHM and MHS are shown that may include camera modules of optical system 300, such as module 200.
Lens 302 includes a plurality of (N) lens elements Li (where "i" is an integer between 1 and N). Here, for example, n=6. Lens 302 is divided into two lens groups, 302-G1 including L1 and L2 and 302-G2 including L3 through L6. For all subsequent optical lens systems, the lens elements within each lens group do not move relative to each other.
L1 is the lens element closest to the object side, and LN is the lens element closest to the image side (i.e., the side on which the image sensor is located). This order is applicable to all lenses and lens elements disclosed herein. 302-G1 has an optical (lens) axis 312 and 302-G2 has an optical axis 314. The lens elements L1 and L2 included in 302-G1 are axially symmetric along OP1 312. The lens elements L3 to L6 included in 302-G2 are axially symmetric along OP2 314. Each lens element Li includes a respective front surface S2i-1 (the index (or subscript) "2i-1" is the number of the front surface) and a respective rear surface S2i (the index "2i" is the number of the rear surface), where "i" is an integer between 1 and N. Such numbering convention is used throughout the specification. Alternatively, as throughout this specification, the lens surface is labeled "Sk", k being from 1 to 2N. The anterior and posterior surfaces may be aspherical in some cases. However, this is not limiting.
As used herein, the term "front surface" refers to the surface of the lens element that is closer to the entrance of the camera (the object side of the camera), and the term "rear surface" refers to the surface of the lens element that is closer to the image sensor (the image side of the camera), for each lens element. For the example of the lens element in fig. 3A, detailed optical data and surface data are given in tables 2 and 3. The values given for these examples are merely illustrative, and other values may be used according to other examples.
The surface types are defined in table 2. The coefficients of the surfaces are defined in table 3. The surface types are:
a) Plano planar surface, no curvature
B) Q type 1 (QT 1) surface elevation (sag) formula:
c) Even aspheric (EVEN ASPHERE (ASP)) surface vector formula:
Where { z, r } is the standard cylindrical polar coordinates (STANDARD CYLINDRICAL polar coordinates), c is the paraxial curvature of the surface (paraxial curvature), k is the conic parameter (conic parameter), rnorm is typically half the clear aperture of the surface, and An is the polynomial coefficient shown in the lens data sheet. The Z-axis is positive towards the image. The value of the aperture radius is given as the clear aperture (or simply "aperture") radius, namely DA/2. The reference wavelength is 555.0nm. Except for refractive Index ("Index") and Abbe number (abbe#), the units are mm.
TABLE 2
Each lens element Li is given in table 2 as having a respective focal length fi. FOV is given as Half FOV (HFOV). The definitions of surface type, Z-axis, DA value, reference wavelength, unit, focal length and HFOV are valid for tables 1 to 13.
In some examples, O-OPFE 304 is a mirror, and the dimensions of O-OPFE 304 are 3.1X3.63 mm (x and y in top view of O-OPFE), and O-OPFE 304 is tilted 45 °. Thereafter, O-OPFE 304 is decentered 0.845mm toward L2Y-such that the center of the O-OPFE is not located at the center of the lens.
In some examples, I-OPFE 306 is a mirror, and the dimensions of I-OPFE 306 are 3.9X3.6 mm (x and y in top view of I-OPFE), and I-OPFE 306 is tilted 45 °. I-OPFE 306 is then decentered 0.451mm toward optical element 307Y-.
TABLE 3 Table 3
Fig. 3B illustrates another 2G optical lens system disclosed herein and designated by reference numeral 320. Lens system 320 is identical to optical lens system 300 except that second lens group 322-G2 is a cut lens obtained by cutting lens group 302-G2 as known in the art. The cut is made only at the bottom side 315 of 322-G2, while the top side 317 of 322-G2 is not cut. As shown in fig. 3B, the cuts allowed smaller MHM and MHS (see table 1). MHM and MHS were reduced by about 10% by cutting.
Fig. 3C illustrates another 2G optical lens system disclosed herein and designated by reference numeral 350. Lens system 350 includes lens 352, O-OPFE 354, I-OPFE 356, optical element 357, and image sensor 358. The lens 352 is divided into two lens groups, 352-G1 including L1 and L2 ("G1") and 352-G2 including L3 through L6 ("G2").
O-OPFE 354 and I-OPFE 356 are both oriented at 45 degrees relative to the y-axis and the z-axis.
The reduction in MHM (relative to optical lens systems 300 and 320) is caused by the fact that the width of O-OPFE 354 can be reduced due to the reduced extremum field entering optical system 350 in the y-direction.
Cutting a first lens group such as 302-G1 by X% will reduce MHM and MHS by about 0.5X% to X%. For example, cutting the first lens group by 20% will reduce MHM and MHS by about 10% to 20%.
In addition to the lens aperture (DA/2, see table 1), the lens elements L1 to L6 included in the optical lens system 350 have the surface types and surface coefficients like the lens elements L1 to L6 included in the optical lens system 300, but in the optical lens system 350, the lens 352 is cut by 20%.352-G1 and 352-G2 are cut along the z-axis and y-axis, respectively. 352-G1 is cut at both sides 362 and 364. 352-G2 is also cut at both sides 366 and 368. The surface types of the optical lens system 350 are defined in table 4. Given the surface type of the non-cutting lens, the aperture radius (DA/2) of the lens element included in the cutting lens 352 is given by:
1. See the values in table 4 in the non-cutting direction (LLi).
2. 80% Of the value of the largest lens element 352-G1 (L1) of the lens elements included in 352-G1 and 352-G2 (L6), respectively, in the cutting direction (LWi) (see Table 4).
Table 4 the cut lens includes one or more lens elements Li that are cut, i.e., that have WLi>HLi (see fig. 3E for an example). Cutting the lens by X% may reduce MHM and/or MHS of a camera module (such as 200 or 250) comprising any of the optical lens systems disclosed herein by about 0.5·x% to X%. For example, the D-cut ratio may be 0% -50%, meaning that WLi may be 0% -50% greater than HLi, i.e., WLi＝HLi to 1.5·hLi. In some examples, a first lens group (such as 352-G1) located at the object side of the O-OPFE and a second lens group (such as 352-G2) located at the image side of the O-OPFE may be cut differently, i.e., the first lens group may have a different D-cut ratio than the second lens group.
Fig. 3D shows a perspective view of a 2G optical lens system 350. 352-G1 cut lens sides 362 and 364 and uncut sides 363 and 365 are visible. Cut lens sides 366 and 368 of 352-G2 and uncut sides 367 and 369 of 352-G2 are also visible.
Fig. 3E shows a top view of element L1 included in 352-G1 of the 2G optical lens system 350. L1 is cut 20%, i.e. its optical width WL1 is 20% greater than its optical height HL1. Since L1 defines the aperture of the lens 352, this means that the aperture diameter DA also changes accordingly, so that the aperture is not axisymmetric. For a cut lens, DA is the effective aperture diameter as defined above.
Due to the D cut, the width of the aperture ("WL") of the lens 352 may be greater than the height "HL", as shown in fig. 3E. HL1 is not measured along the z-axis, e.g., for the optical height of the lens element included in 352-G2 or lens element of lens 104 (see fig. 1A), HL1 is measured along the y-axis. Thus, HL1 is not limited by MHM, i.e., a lens (such as lens 352) may support embodiments that satisfy HL1>MHS, i.e., a greater aperture height (measured along the z-axis) than the module shoulder, as opposed to known folded camera 100. This is beneficial in terms of image quality of a camera including the optical system disclosed herein because it can overcome the geometric limitations of the lens included in the module shoulder (i.e., HL<MHS), such as shown for the known folded camera 100 shown in fig. 1A. A large aperture height allows for a larger effective DA, resulting in a lower f/#, which is beneficial because it allows more light to enter the camera in a given time interval. The definition and explanation given in fig. 3E for optical lens system 350 is also valid for all other optical lens systems disclosed herein.
Fig. 4 shows another 2G optical lens system, generally designated 400. Lens system 400 includes a lens 402, an O-OPFE 404 (e.g., a prism or mirror), an I-OPFE 406 (e.g., a prism or mirror), an optical element 407, and an image sensor 408. Both O-OPFE 404 and I-OPFE 406 are oriented at 45 degrees relative to the y-axis and the z-axis. Lens 402 is divided into G1 (including L1 and L2) and G2 (including L3 to L6). In some examples, 402-G1 and/or 402-G2 may be dicing shots, as in the examples above. Detailed optical data and surface data of the optical lens system 400 are given in tables 5 and 6. O-OPFE 404 may be a mirror having dimensions of 7.4mm by 7.82mm (measured in the O-OPFE plane). I-OPFE 406 may be a mirror having dimensions of 8.4mm by 7.86mm (measured in the I-OPFE plane). The thickness with respect to the plurality of OPFEs is the thickness with respect to the optical axis. In some examples, lens 402 may be cut as shown in FIG. 3B, such that O-OPFE 404 and I-OPFE 406 determine MHM and MHS, as described for MHM -cut and MHS -cut. For such an example, MHM -cut = 8.85mm, and MHS -cut = 6.35mm (as shown).
TABLE 5
TABLE 6
Watch 6 (subsequent)
Fig. 5 shows a "group 1" (or "1G") optical lens system, numbered 500, comprising a lens 502 with n=4 lens elements, an O-OPFE 504, an I-OPFE 506, an optical element 507, and an image sensor 508. The lens 502 is not divided into two lens groups, but all 4 lens elements are located at the object side of the O-OPFE 504.
Detailed optical data and surface data of the optical lens system 500 are given in tables 7 and 8. Both O-OPFE 504 and I-OPFE 506 may be mirrors. The dimensions of O-OPFE 504 and I-OPFE 506 are 5.0mm by 5.2mm (measured in the OPFE plane). The thickness with respect to the mirror is the thickness with respect to the optical axis. O-OPFE 504 and I-OPFE 506 are inclined 45 degrees relative to OP1 and OP 2.
In some examples of 1G optical lens systems such as 500, 600, and 700, the lens may be a cut lens as seen in the examples above. By cutting along the z-axis, lower MHM and MHS may be achieved by reducing the size of the O-OPFE and the size of the I-OPFE. Cutting the lens by X% will reduce MHM and MHS by about 0.5X% to X%. For example, cutting the lens by 20% will reduce MHM and MHS by about 10% to 20%.
TABLE 7
TABLE 8
Table 8 (subsequent)
Fig. 6 shows another 1G optical lens system, numbered 600, comprising a lens 602 with n=4 lens elements, an O-OPFE 604, an I-OPFE 606, an optical element 607 and an image sensor 608. All 4 lens elements of lens 602 are located at the object side of O-OPFE 604. The detailed optical data and surface data of the optical lens system 600 are given in tables 9 and 10. Both O-OPFE 604 and I-OPFE 606 may be mirrors. The dimensions of O-OPFE 604 are 8.0mm by 6.1mm (measured in the O-OPFE plane). The dimensions of I-OPFE 606 are 9.6mm×7.9mm (measured in the I-OPFE plane). The thickness with respect to the plurality of OPFEs is the thickness with respect to the optical axis. O-OPFE 604 is tilted by α=43 degrees with respect to the y-axis. I-OPFE 606 is tilted by β=47 degrees with respect to the y-axis.
TABLE 9
Table 10
Watch 10 (Xue)
Fig. 7A shows yet another 1G optical lens system, numbered 700, that includes a lens 702 having n=4 lens elements, an O-OPFE 704, an I-OPFE 706, an optical element 707, and an image sensor 708. All 4 lens elements are located at the object side of O-OPFE 704.
The detailed optical data and surface data of the optical lens system 700 are given in tables 11 and 12. O-OPFE 704 can be a mirror and I-OPFE 706 can be a prism. The dimensions of O-OPFE 704 are 6.2mm by 4.64mm (measured in the O-OPFE plane). The dimensions of I-OPFE 706 are 6.7mm×9.16mm (measured in the I-OPFE plane). O-OPFE 704 and I-OPFE 706 are tilted 45 degrees with respect to the y-axis. O-OPFE 704 is a mirror and I-OPFE 706 is a prism.
The prism 706 includes an object side bottom stray light prevention mechanism 732, an object side top stray light prevention mechanism 734, an image side bottom stray light prevention mechanism 722, and an image side top stray light prevention mechanism 724.
TABLE 11
Table 12
Watch 12 (Xuezhi)
Fig. 7B shows a side view of the prism 706. Fig. 7C shows a perspective view of the prism 706. The object side bottom stray light prevention mechanism 732 and the object side top stray light prevention mechanism 734 are stray light prevention shields. This means that no light enters the prism 706 where the stray mask 732 and the stray mask 734 are located, but only light entering in an optically effective (active) way is 736. The image side bottom stray light prevention mechanism 722 and the image side top stray light prevention mechanism 724 are geometric stray light prevention mechanisms, which are hereinafter referred to as "stray light prevention frames".
The prism 706 has a prism height ("HP") and an optical (or optically effective) prism height ("HP-O") measured along the z-axis, a prism length ("LP") measured along the y-axis, and a prism width ("WP") measured along the x-axis. The bottom stray light prevention rack 722 and the top stray light prevention rack 724 have lengths (length "LBS" and "LTS" for "bottom rack" and "top rack", respectively) and heights (HBS "and HTS", respectively). The bottom and top stray light prevention masks 732 and 734 have a height "HBM" of "bottom mask" and a height "HTM" of "top mask", respectively. Values and ranges are given in mm in table 13.
Stray light prevention mechanisms are beneficial because they prevent stray light from reaching an image sensor, such as image sensor 708. Stray light is unwanted light emitted or reflected from objects in the scene that enters the aperture (or iris) of the camera and reaches the image sensor in a different (or desired) light path than the planned (or desired) light path. The planned light path is described as follows:
1. light is emitted or reflected by objects in the scene.
2. Light enters the aperture (or iris) of the camera and passes through all surfaces of the lens (for a 1G optical lens system) or G1 of the lens (for a 2G optical lens system).
3. For example, in the case where O-OPFE is a mirror, the light is reflected once. For example, where the O-OPFE is a prism, light passes once through the object side surface of the O-OPFE, is reflected once (as shown by the optical lens system disclosed herein), and then passes once through the image side surface of the O-OPFE.
4. For a 2G optical lens system, light passes through all surfaces of the lens G2 at once.
5. For example, in the case where the I-OPFE is a mirror, the light is reflected once. For example, where the I-OPFE is a prism, light passes once through the object side surface of the I-OPFE, is reflected once (as shown by the optical lens system disclosed herein), and then passes once through the image side surface of the I-OPFE.
6. The light is irradiated onto the image sensor.
Light reaching the image sensor on any light path other than the above-described planned light path is considered undesirable and is referred to as stray light.
| Numerical value | Numerical range |
| HP | 5.2 | 3-10 |
| HP-O | 3.5 | 2-10 |
| LP | 6.5 | 4–12.5 |
| WP | 7.1 | 4–12.5 |
| HBS | 0.18 | 0.05–1 |
| LBS | 1.45 | 0.25–5 |
| HTS | 0.85 | 0.2–4 |
| LTS | 0.85 | 0.2–4 |
| HBM | 0.4 | 0.2–3 |
| HTM | 1.3 | 0.5–4 |
TABLE 13
Fig. 8A schematically illustrates a method for focusing (or "autofocus" or "AF") in the optical lens system disclosed herein.
Focusing of 1G optical systems
Lens 802 and O-OPFE 804 move linearly together along the y-axis relative to non-moving I-OPFE 806 and image sensor 808. Block 812 indicates the component movement for performing AF, and arrow 814 indicates the direction of movement for performing AF. An actuator known in the art, such as a Voice Coil Motor (VCM) or stepper motor, may be used to actuate this motion as well as all other motions described in fig. 8A-8C.
Further, the 1G optical lens system may perform focusing and OIS, like a conventional (or "vertical" or "unfolded") camera such as wide-angle camera 130. Specifically, the 1G optical lens system may be focused by merely moving the lens (such as lens 802) along an axis parallel to the z-axis relative to all other camera components, i.e., lens 802 is moved along the z-axis relative to O-OPFE 804, I-OPFE 806, and image sensor 808. To perform OIS along the first OIS axis, only the lens 802 may be moved relative to all other camera components along an axis parallel to the y-axis. To perform OIS along the second OIS axis, the lens 802 may be moved relative to all other camera components along an axis perpendicular to both the y-axis and the z-axis.
Focusing of 2G optical systems
The first lens group (such as lens group 302-G1 for example), the O-OPFE (such as O-OPFE 304), and the second lens group (such as lens group 302-G2 for example) move together along the y-direction. I-OPFE (such as I-OPFE 306) and image sensor (such as image sensor 308) do not move.
Fig. 8B schematically illustrates a method for performing optical image stabilization (optical image stabilization, OIS) in a first OIS direction for the optical lens system disclosed herein.
OIS in first direction in 1G optical lens system
Lens 802, O-OPFE 804, and I-OPFE 806 move linearly together along the y-axis relative to non-moving image sensor 808. Block 816 indicates the component movement for performing OIS in the first OIS direction and arrow 818 indicates the movement direction for performing OIS in the first OIS direction.
OIS in first direction in 2G optical lens system
The first lens group, such as 302-G1, O-OPFE (such as O-OPFE 304), the second lens group (such as 302-G2), and I-OPFE (such as I-OPFE 306) move together in the y-direction. The image sensor (such as image sensor 308) does not move. In other 2G optical lens systems, only the first lens group (such as 302-G1), the O-OPFE (such as O-OPFE 304), and the second lens group (such as 302-G2) are moved relative to the I-OPFE (such as I-OPFE 306) and relative to the image sensor (such as image sensor 308).
Fig. 8C schematically illustrates a method of performing OIS in a second OIS direction for an optical lens system disclosed herein.
OIS in second direction in 1G optical lens system
Lens 802, O-OPFE 804, and I-OPFE 806 move linearly with respect to non-moving image sensor 808 vertically with the y-z coordinate system shown. Block 816 indicates the component movement for performing OIS in the second OIS direction and arrow 822 indicates the direction of movement for performing OIS in the second OIS direction. Arrow 822 points in a direction perpendicular to the y-z coordinate system shown.
OIS in second direction in 2G optical lens system
The first lens group (such as 302-G1), the O-OPFE (such as O-OPFE 304), the second lens group (such as 302-G2), and the I-OPFE (such as I-OPFE 306) move linearly with respect to the non-moving image sensor (such as image sensor 308) perpendicular to the y-z coordinate system shown. In other 2G optical lens systems, only the first lens group (such as 302-G1), the O-OPFE (such as O-OPFE 304), and the second lens group (such as 302-G2) are moved relative to the I-OPFE (such as I-OPFE 306) and relative to the image sensor (such as image sensor 308).
It is appreciated that certain features of the disclosed subject matter, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the disclosed subject matter, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination.
Unless otherwise indicated, the use of the expression "and/or" between the last two elements of the list of options for selection indicates that the selection of one or more of the listed options is appropriate and may be made.
It should be understood that when the claims or the specification refer to "a" or "an" element, such recitation should not be interpreted to mean that there is only one of the element.
Furthermore, for the sake of clarity, the term "substantially" is used herein to connote the possibility of a change in value within an acceptable range. According to an example, the term "substantially" as used herein should be interpreted to imply a possible variation of up to 5% above or below any given value. According to another example, the term "substantially" as used herein should be interpreted to imply a possible variation of up to 2.5% above or below any given value. According to another example, the term "substantially" as used herein should be interpreted to imply a possible variation of up to 1% above or below any given value.
All patents and patent applications mentioned in this specification are herein incorporated by reference in their entirety to the same extent as if each individual patent or patent application was specifically and individually indicated to be incorporated by reference. Furthermore, citation or identification of any reference in this disclosure shall not be construed as an admission that such reference is available as prior art to the present disclosure.